Fair Value of Financial Instruments (Details 2) (USD $)	Sep. 30, 2011	Dec. 31, 2010
Assets and liabilities measured at fair value on a recurring basis
Securities available-for-sale	$ 786,195,000	$ 838,894,000
Residential mortgage-backed securities, at estimated fair value	88,209,000	93,929,000
Equity investments, at estimated fair value	170,175,000	99,955,000
Loans held for sale, carrying value	500,490,000	463,628,000
Loans held for sale, amortized cost	103,400,000	194,500,000
Interest rate swaps \| Recurring basis \| Significant Other Observable Inputs (Level 2)
Assets and liabilities measured at fair value on a recurring basis
Derivative liability, fair value	(100,849,000)	(58,365,000)
Interest rate swaps \| Recurring basis \| Estimated Fair Value
Assets and liabilities measured at fair value on a recurring basis
Derivative liability, fair value	(100,849,000)	(58,365,000)
Commodity swaps \| Recurring basis \| Significant Other Observable Inputs (Level 2)
Assets and liabilities measured at fair value on a recurring basis
Derivative asset, fair value	3,322,000
Derivative liability, fair value		(226,000)
Commodity swaps \| Recurring basis \| Estimated Fair Value
Assets and liabilities measured at fair value on a recurring basis
Derivative asset, fair value	3,322,000
Derivative liability, fair value		(226,000)
Credit default swaps-protection sold \| Recurring basis \| Significant Other Observable Inputs (Level 2)
Assets and liabilities measured at fair value on a recurring basis
Derivative asset, fair value		492,000
Derivative liability, fair value	(3,653,000)
Credit default swaps-protection sold \| Recurring basis \| Estimated Fair Value
Assets and liabilities measured at fair value on a recurring basis
Derivative asset, fair value		492,000
Derivative liability, fair value	(3,653,000)
Total rate of return swaps \| Recurring basis \| Significant Unobservable Inputs (Level 3)
Assets and liabilities measured at fair value on a recurring basis
Derivative asset, fair value	159,000	104,000
Total rate of return swaps \| Recurring basis \| Estimated Fair Value
Assets and liabilities measured at fair value on a recurring basis
Derivative asset, fair value	159,000	104,000
Foreign exchange forward contracts \| Recurring basis \| Significant Other Observable Inputs (Level 2)
Assets and liabilities measured at fair value on a recurring basis
Derivative liability, fair value	(16,004,000)	(17,296,000)
Foreign exchange forward contracts \| Recurring basis \| Estimated Fair Value
Assets and liabilities measured at fair value on a recurring basis
Derivative liability, fair value	(16,004,000)	(17,296,000)
Foreign exchange options \| Recurring basis \| Significant Unobservable Inputs (Level 3)
Assets and liabilities measured at fair value on a recurring basis
Derivative asset, fair value	15,909,000	14,791,000
Foreign exchange options \| Recurring basis \| Estimated Fair Value
Assets and liabilities measured at fair value on a recurring basis
Derivative asset, fair value	15,909,000	14,791,000
Common stock warrants \| Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets and liabilities measured at fair value on a recurring basis
Derivative asset, fair value	1,046,000
Common stock warrants \| Recurring basis \| Significant Unobservable Inputs (Level 3)
Assets and liabilities measured at fair value on a recurring basis
Derivative asset, fair value	2,179,000	3,453,000
Common stock warrants \| Recurring basis \| Estimated Fair Value
Assets and liabilities measured at fair value on a recurring basis
Derivative asset, fair value	3,225,000	3,453,000
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets and liabilities measured at fair value on a recurring basis
Securities available-for-sale	5,417,000	3,374,000
Equity investments, at estimated fair value	1,231,000
Asset, fair value	7,694,000	3,374,000
Liabilities, fair value	(1,192,000)
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Securities sold, not yet purchased
Assets and liabilities measured at fair value on a recurring basis
Securities sold, not yet purchased	(1,192,000)
Recurring basis \| Significant Other Observable Inputs (Level 2)
Assets and liabilities measured at fair value on a recurring basis
Securities available-for-sale	712,831,000	752,423,000
Equity investments, at estimated fair value	34,971,000	15,023,000
Asset, fair value	751,124,000	767,938,000
Liabilities, fair value	(120,506,000)	(75,887,000)
Recurring basis \| Significant Unobservable Inputs (Level 3)
Assets and liabilities measured at fair value on a recurring basis
Securities available-for-sale	67,947,000	83,097,000
Residential mortgage-backed securities, at estimated fair value	88,209,000	93,929,000
Equity investments, at estimated fair value	133,973,000	84,932,000
Asset, fair value	310,082,000	280,306,000
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Other Assets
Assets and liabilities measured at fair value on a recurring basis
Other assets	1,706,000
Recurring basis \| Estimated Fair Value
Assets and liabilities measured at fair value on a recurring basis
Securities available-for-sale	786,195,000	838,894,000
Residential mortgage-backed securities, at estimated fair value	88,209,000	93,929,000
Equity investments, at estimated fair value	170,175,000	99,955,000
Asset, fair value	1,068,900,000	1,051,618,000
Liabilities, fair value	(121,698,000)	(75,887,000)
Recurring basis \| Estimated Fair Value \| Other Assets
Assets and liabilities measured at fair value on a recurring basis
Other assets	1,706,000
Recurring basis \| Estimated Fair Value \| Securities sold, not yet purchased
Assets and liabilities measured at fair value on a recurring basis
Securities sold, not yet purchased	(1,192,000)
Non-recurring basis \| Significant Other Observable Inputs (Level 2)
Assets and liabilities measured at fair value on a recurring basis
Loans held for sale	397,115,000	254,682,000
Asset, fair value	397,115,000	254,682,000
Non-recurring basis \| Significant Unobservable Inputs (Level 3)
Assets and liabilities measured at fair value on a recurring basis
Loans held for sale		14,443,000
Private equity investments, at cost		1,800,000
Asset, fair value		16,243,000
Non-recurring basis \| Estimated Fair Value
Assets and liabilities measured at fair value on a recurring basis
Loans held for sale	397,115,000	269,125,000
Private equity investments, at cost		1,800,000
Asset, fair value	$ 397,115,000	$ 270,925,000

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The fair value of other assets.

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Represents the fair value of investments held in private equity funds as of the balance sheet date.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The fair value as of the balance sheet date of firm holdings in corporate stocks (common and preferred), stock options, warrants and any other financial instrument which represents, or provides the ability to obtain, ownership rights in a corporation. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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The fair value as of the balance sheet date of firm holdings in mortgages, mortgage backed securities (investment instruments that represent ownership of an undivided interest in a group of mortgages, where principal and interest from the individual mortgages are used to pay investors' principal and interest on the mortgage backed security) and asset-backed securities that are primarily paid from the cash flows of a discrete pool of receivables or other financial assets (such as credit-card receivables), either fixed or revolving, that by their terms convert into cash within a finite time period. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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This element represents the aggregate of the liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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